1 files changed, 50 insertions, 0 deletions
diff --git a/color.c b/color.c
new file mode 100644
index 0000000..f713451
--- /dev/null
+++ b/color.c
@@ -0,0 +1,50 @@
+/* Copyright (C) 2019  C. McEnroe <june@causal.agency>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <stdint.h>
+
+#include "chat.h"
+
+// Adapted from <https://github.com/cbreeden/fxhash/blob/master/lib.rs>.
+static uint32_t hashChar(uint32_t hash, char ch) {
+	hash = (hash << 5) | (hash >> 27);
+	hash ^= ch;
+	hash *= 0x27220A95;
+	return hash;
+}
+
+enum IRCColor colorGen(const char *str) {
+	if (!str) return IRCDefault;
+	uint32_t hash = 0;
+	for (; str[0]; ++str) {
+		hash = hashChar(hash, str[0]);
+	}
+	while (IRCBlack == (hash & IRCLightGray)) {
+		hash = hashChar(hash, '\0');
+	}
+	return (hash & IRCLightGray);
+}
+
+static enum IRCColor colors[TagsLen];
+
+struct Tag colorTag(struct Tag tag, const char *gen) {
+	if (!colors[tag.id]) colors[tag.id] = 1 + colorGen(gen);
+	return tag;
+}
+
+enum IRCColor colorFor(struct Tag tag) {
+	return colors[tag.id] ? colors[tag.id] - 1 : IRCDefault;
+}